The yacht acts as Colonel Cortez's home while he stays in Vice City and is also the center of his criminal operations, which range from cocaine trafficking to governmental espionage. The boat is also the site of Cortez's infamous parties, which are thrown often on the ship's deck and frequently recieve several of Vice City's most famous celebrities and most notorious criminals as guests. Such guests have included the likes of Ricardo Diaz, Jezz Torrent, Avery Carrington and many more.
It is from this yacht that Colonel Cortez gives all his missions to Tommy Vercetti over the course of the game. After the Colonel leaves Vice City during the mission All Hands On Deck, the boat is not seen again, but strangely, it will still appear on the map as a static object or a building.